UI: Improve Streamlit onboarding, UX, and error handling

[Sandeep-Kumar-930]

Summary

This PR improves the Streamlit web interface to make the project more beginner-friendly and robust without modifying any core ML or emotion-detection logic.

Changes Made

• Added clear onboarding instructions for first-time users
• Improved page title, layout, and overall UI clarity
• Added safe error handling for missing model files and webcam access
• Minor UX refinements for buttons and layout consistency

Testing

• Manually tested Streamlit UI
• Verified application starts without errors
• Confirmed no changes to emotion detection or model logic

Notes

This PR aligns with project goals of improving usability, onboarding, and real-world open-source contribution quality.

[vercel]

@Sandeep-Kumar-930 is attempting to deploy a commit to the Shivam Gupta's projects Team on Vercel.

A member of the Team first needs to authorize it.

[Sandeep-Kumar-930]

Hi maintainers 👋

The failing Vercel check seems to be due to deployment authorization on forks.
This PR only contains UI and onboarding improvements and does not affect deployment logic.

Please let me know if any changes are needed from my side.
Thanks for reviewing!

[Sandeep-Kumar-930]

Hyy Admin PlS Merged My PRs And Add on My profile, Pls count it

[Sandeep-Kumar-930]

Hi @Shivamgupta4651,

Thanks for reviewing and approving the PR 🙏

It looks like the Vercel check is failing due to fork deployment authorization.
Since this PR only contains UI and onboarding improvements and does not affect build configuration, could you please advise whether the check can be re-run or temporarily bypassed?

Happy to make any required adjustments.

Thank you!